Lady Gaga returned to Lollapalooza this past weekend for the first time since 2007, and it's safe to say the crowd was just a bit bigger this time around. Gaga went from playing a humble singer-songwriter set on a side stage to opening the festival, bringing in a "massive" special stage with her that event founder and Jane's Addiction frontman Perry Ferrell admittedly invested hundreds of thousands of dollars into. "Only Lady Gaga could step in and say 'I'm a headliner,'" Ferrell told Britain's Daily Star.

Gaga may have upgraded but she certainly hasn't lost her rock-and-roll spirit. After her own extravagant set, Gaga surprised Semi Precious Weapons fans by joining the band on-stage during their performance and causing a near riot. Wearing little more than fishnet stockings and strategic golden pasties, Gaga rocked out on drums before stage diving into the unsuspecting crowd and, to the dismay of her bodyguard, crowd surfing around for a bit. Check out the video below (**Warning: NSFW**).